Conventionally, before emitting so-called “industrial waste gases” and/or “process gases”, air purification is performed to remove various types of fine particulates contained in the industrial waste gases, such as mist and dust containing sticky and abrasive particulate powders, which pollute the atmosphere, and/or process gases containing similar particulate which could damage process equipment used in the wood, pharmaceutical and mining industries, for example.
Previous air stream filtration methods include, for example, electrostatic dust precipitators, cyclone separator systems, and rigid ceramic filters, each of which has suffered from certain drawbacks and inefficiencies. The cleaning of the collection plates in electrostatic precipitators presents a problem inasmuch as a substantial amount of reentrainment of the dust occurs. In cyclone separators, the particulate laden gas is introduced under pressure, and thus vessel pressure and “collapsing pressure” due to pressure loss through the cyclone system are a common cause of concern. Ceramic filter devices on the other hand comprise porous ceramic materials which, when subjected to high temperature corrosive environments, the filter elements can break under the influence of these conditions.
It is an object of the disclosure herein to provide a hot gas filtration system with improved reliability and efficiency, and in particular, a hot gas filtration system capable of filtering air streams that are high temperature, high velocity, high moisture and carrying sticky or abrasive particulates.